Method of treating molten magnesium



Patented June 9, 1925.

umrsn GUSTAV SCHREIBER, OF GRIESHEIM-ON-THE-MAIN, AND'ADOLF BECK. 01E SCHWAN- HEM-ON-THE-MAIN, GERMANY, ASSIGNOR-S TO CHEMI SCHE FABRIK GBIESHEIM ELEKTRON, F FRANKFORT-ON-THE-MAIN, GERMANY.

METHOD OF TREATING MOLTEN MAGNESIUM.

No Drawing. I

Z '0 all whom it may concern: 1

Be it known that we, GUSTAV SCHREIBER and AnoLF BECK, citizens of Germanyyresida ing at Griesheim-on-the-Main and Schwan- 5 heim-on-theMain, Germany, respectively, have invented certa n new and useful-Improvements in Methods of Treating Molten Magnesium, of which the following is a specification. 1o

ing molten magnesium and its alloys with a'view to protecting .them against oxida tion.

In treating and handling magnesium and alloys rich in magnesium in molten condition, it is important that the'metal 'or alloy treated be protected against oxidation. This is not only 'a question of protecting them against an oxidation resulting in a burning of the metalwithan open flame, but also against slow oxidations causing films of an oxid to be formed on the metal. films impair the quality of the metal as hey interrupt the homogeneity of the metal and ished articles.

We have ascertained that it is possible to absolutely prevent oxidation of magnesium and its alloys b placing sulphur on the bright surface 0 the metal, provided that this be done at temperatureswhich are near or above the melting point, butnot so high as to cause the metal to react with the sulphur. lVc have observed that this range of temperatures is wide enough to permit the slight overheating of the metal beyond the melting point which is required as a rule in all casting operations;

The effective principle underlying our in-f 40 vention consists in causing an atmosphere of sulphur vapour to be formed above the metal, another atmosphere of SO: being formed above the first atmosphere by combustion.

of the metal in different manner, either in solid or in molten condition or as vapour. We have found it to be preferable to dust or spray the sulphur onto the metal, for instance by dusting fine sulphur powder through a linen bag by shaking. We may, however, also direct a. spray comprising sulphur powder against the metal. The dusting or spraying can be effected while the The invention refers to a method of treat- All such reduce its mechanical strength in the fin-- Jnot deslre to be limited to the exact means The sulphur can be placed on thesurface Application filed October 29, 1923. Serial No. 671,403.

'of sulphur powder being then directed onto the crucibles, the flowing metal and the molds.

We have further utilized our novel method as a means for extinguishing the flame of burning magnesium or magnesium alloys. It is true that the parts of the metal which are already burning willreact with the sulphur, magnesium sulfide being formed, but that portion of the metal which is merely heated and in the course ofmelting down, is protected by the sulphur against catching fire, so that fires arising in crucibles or in the heaps of metal chips which have caught fire can easily and safely be extinguished. In the latter case, it is not always necessary to employ only sulphur; we' have found that in such a case the sulphur can be diluted by additions of inert materials, such as maggesia or sand whichneed not. be perfectly We wish it to be understood that we do prising placing sulphur powder onto the surface of the molten metal.

3. The method of protecting molten magnesium and its alloys against burning comprising spraying sulphur powder onto the surface of the molten metal.

4. The method of protecting molten magnesium and its alloys against binning comprising spraying a mixture of sulphur powder and an inertmaterial onto the surface of the molten metal.

In testimony whereof we afiix our signatures.

GUSTAV SCHREIBER.

. ADOLF BECK.

Witnesses: I

IVAN LAVRETOKY, H. SCHICHERT. 

